libgit2 is...
licensed under a very permissive license so you can use it anywhere
faster than any other Git library
written in standards compliant C99
completely multi-platform: Windows, Linux, Mac OS X, xBSD
compiled natively under all platforms (yes, even MSVC on Windows)
re-entrant, with sane error handling
designed with a solid and consistent API
available as bindings for all major scripting languages
WWW: http://libgit2.github.com/

Remove CMAKE_USE_PTHREAD from the ports using it.
This setting has not had any effect since r1.13 to bsd.cmake.mk, as it
was only useful when we supported FreeBSD < 7.
Approved by: avilla (mentor), portmgr (miwi)
Feature safe: yes

libgit2 is...
licensed under a very permissive license so you can use it anywhere
faster than any other Git library
written in standards compilant C99
completely multi-platform: Windows, Linux, Mac OS X, xBSD
compiled natively under all platforms (yes, even MSVC on Windows)
re-entrant, with sane error handling
designed with a solid and consistent API
available as bindings for all major scripting languages
WWW: http://libgit2.github.com/